1. Field of the Invention
The present invention relates to an optical disk recording and reproducing apparatus using a write-once type optical disk as a recording medium and a method for recording and controlling an optical disk.
2. Description of the Related Art
As an optical disk which is capable of recording data, a write-once type optical disk is known which uses an organic pigment in a recording layer thereof. As such write-once type optical disk, there is available a CD-R (recordable) or the like.
In order to record data with respect to the write-once type optical disk, for example, data to be written which is output, for example, from a personal computer or the like is temporarily stored in a buffer circuit. Then, data stored in the buffer circuit is subsequently read, and a synchronous signal, sub-code data, an error correction code or the like is added, and the EFM (Eight to Fourteen Modulation) conversion is conducted. Furthermore, after converting data to a record pulse signal, data is recorded by supplying data with the laser pickup.
In a write-once type optical disk such as a CD-R or the like, a buffer underrun state is generated in which the data transmission rate of the input data is delayed at the time of supplying data to the buffer circuit as compared with the data transmission rate at the time of recording data on the disk. When the buffer underrun state is generated, the record data is interrupted and the buffer underrun is generated. Optical disks such as disk-at-once type disks and track-at-once disks in which file groups to be written are designated in advance cannot be used any more, and such disks must be discarded.
Jpn. Pat. Appln. KOKAI Publication No. 2000-4030 describes a technique for restarting from the front of non-recorded area an operation of writing data which continues to data which is written immediately before interruption at the time when the data writing operation to the disk is suspended and the remaining amount of data of the buffer circuit becomes sufficient upon the detection of the fact that the remaining amount of data in the buffer circuit becomes small.
An optical disk recording and reproducing apparatus according to an aspect of the present invention comprises:
a buffer circuit configured to receive and store data input via an interface and output the stored data;
an EFM modulation circuit connected to the buffer circuit for receiving data output from the buffer circuit, adding at least a frame synchronous signal and sub-code data with respect to the data, subjecting these items of data to the EFM modulation to create record data to be recorded on an optical disk;
a buffer remaining amount control circuit connected to the interface and the EFM modulation circuit for detecting the remaining amount of data stored in the buffer circuit;
a record control circuit connected to the EFM modulation circuit and the buffer remaining amount control circuit for conducting the control for temporarily suspending the recording operation with respect to the optical disk at an arbitrary position of the main data of the record data excluding the frame synchronous signal and the sub-code data in the case where the detection result of the remaining amount of data in the buffer remaining amount control circuit corresponds to the state in which a data transmission rate of an input data to the buffer circuit is lower than a data transmission rate of an output data from the buffer circuit to the EFM modulation circuit at a time of recording data on the optical disk; and
a record restarting position detection circuit connected to the record control circuit for receiving data obtained by reproducing the optical disk on which the recording operation is temporarily suspended in the midst of recording the record data and detecting the position of the disk on which the recording operation is temporarily suspended;
wherein the record control circuit conducts a control for restarting a recording operation with respect to the optical disk from the record restarting position on the disk detected with the record restarting position detection circuit in the case where the detection result of the remaining amount of data in the buffer remaining amount detection circuit corresponds to the state in which the data transmission rate of the input data to the buffer circuit is higher than the data transmission rate of the output data from the buffer circuit to the EFM modulation circuit.
A method for recording and controlling an optical disk according to another aspect of the present invention comprises:
storing input data in a buffer circuit and outputting the stored data from the buffer circuit;
adding at least a frame synchronous signal and sub-code data to data output from the buffer circuit and further subjecting data to the EFM modulation to create record data which is to be recorded on an optical disk;
judging the remaining amount of data stored in the buffer circuit for temporarily suspending the recording operation with respect to the optical disk at an arbitrary position of the main data of the record data excluding the frame synchronous signal and the sub-code data in the case where the remaining amount of data provides a state in which a data transmission rate of the input data to the buffer circuit is lower than the output data from the buffer circuit;
detecting the position of the disk on which the recording operation is temporarily suspended by the reproduction of the optical disk in the case where the state in which the data transmission rate of the input data to the buffer circuit is higher than the output data from the buffer circuit; and
restarting the recording operation of new record data so that the new data continues to the end of the record data on the optical disk which data is generated in the temporary suspension.